Wrapping methods up in a JavaScript object

Question

I have the need to do something like this:

<script src="apiWrapper.js"></script>
<script>
  apiWrapper.init('api_key');
  apiWrapper.doSomethingElse();
</script>

Essentially, have a singleton style object in a page that I can add methods and properties too and have available from anywhere within the page.

What's the best way to do this?

possible duplicate of [Simplest/Cleanest way to implement singleton in JavaScript?](http://stackoverflow.com/questions/1479319/simplest-cleanest-way-to-implement-singleton-in-javascript) — Alex K., Jul 31 '13 at 12:54
For patterns like that it can be a pain if you have to check for the init state in subsequent calls, so personally I prefer `var myApi = ApiWrapper.init(apikey);` — Alex K., Jul 31 '13 at 12:57
Is it possible you're overthinking the singleton idea. Can't you just declare a global object that contains the properties you need? — Splendiferous, Jul 31 '13 at 13:02

kamituel · Accepted Answer · 2013-07-31T12:59:40.757

3

You could use this approach (which gives you a way of having private properties/functions):

var apiWrapper = apiWrapper || (function () {

  /* private functions here */
  var privateFunction = function () {
  }

  /* public functions here */
  return {
    init: function (opts) {},
    doSomethingElse: function () {}
  };
})();

edited Jul 31 '13 at 12:59

answered Jul 31 '13 at 12:53

kamituel

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score 1 · Answer 2 · answered Jul 31 '13 at 12:53

I use this structure for my scripts too:

apiWrapper.js:

var apiWrapper = apiWrapper || {};

apiWrapper = {
    doSomethingElse: function() {

    },
    init: function(options) {

    }
};

If you want to do function chaining (like jQuery), simply return this; at the end of the functions you wish to chain.

score 0 · Answer 3 · answered Jul 31 '13 at 13:01

<script>
...
    // create your singleton in the global scope
    if(!("apiWrapper" in window))
        window.apiWrapper = {};
    ...
    // use your singleton object
    apiWrapper.init = function() {...};
    apiWrapper.prop = 123;
    ...
    apiWrapper.init();
</script>

Wrapping methods up in a JavaScript object

3 Answers3